Apparatus for vulcanizing articles



Filed Jan. 1- 1., 1945 Feb. 15,1949 A, N, G AY 2,461,600

APPARATUS FOR VULCANiZING ARTICLES 2 Sheets-Sheet l Feb. 15, 1949. A. N. GRAY 2,461,600

v APPARATUS FOR VULCANIZING ARTICLES Filed Jan. 11, 1945 2 Sheets-Sheet 2 lNl/ENTOR /v. GRAY ATTORNEY Patented- Feb. 15, 1949 2,461,600 APPARATUS FOR VULCANIZIN G ARTICLES Alvin N. Gray,

Joppa, Md., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application January 11, 1945, Serial No. 572,324

' 3 Claims. (01. 18-43) This invention relates to apparatus for vulcanizing articles.

In the manufacture of field cables having loading coils thereon, the coils are placed upon the cables and a protective covering of insulating material is formed and vulcanized thereover. During the vulcanization of the covers they are subjected to great compression and high temperatures and heavy mold sections must be used to perform this operation. As a result of the vulcanization step, hot gases are formed in the material being vulcanized and if such heavy mold sections are opened after a vulcanizing operation before the hot gases are cooled, the gases 'will burst the vulcanized material. If the mold sections are kept closed until the gases in the vulcanized material are cooled, the heavy mold sections also are cooled and must be reheated for another vulcanizing operation, which causes the vulcanizing operation to be time consuming and costly.

An object of the invention is to provide new and improved apparatus for vulcanizing articles.

One apparatus embodying the invention comprises a pair of heavy mold sections having recesses formed therein, a pair of complementary shells which are designed to fit into the recesses, and means for clamping the shells together.

A complete understanding of the invention may be obtained from the following detailed description of an apparatus forming specific embodiments thereof, when read in conjunction with the appended drawings, in which:

Fig. 1 is a partially sectional, perspective view an apparatus embodying the invention;

Fig. 2 is an exploded, perspective view of a portion of the apparatus;

Fig. 3 is a vertical, sectional view of a cooling tank for carrying out a step of a method eifected by the apparatus and a portion of the apparatus;

Fig. 4 is a fragmentary, front view of the ap paratus in a vulcanizing press, and

Fig. 5 is a view of an article produced by the apparatus.

Referring now in detail to the drawings, there is shown therein an apparatus for forming an insulating and weatherproofing cover around a loading coil in (Fig. 2) positioned on a cable II, which apparatus includes identical thin shells l2 and 13. The shell l3 provided with an-enlarged molding cavity l4 tapering to cylindrical grooves l5 and H5 at the ends thereof has flanges l1 and I8 formed on the ends thereof. The shell l2, which has a molding cavity (not shown) identical with the molding cavity I4 and grooves identical with the grooves 15 and I6 formed therein, is provided with flanges 20 and 2| on the ends thereof. The flanges 2B and 2| have slots 22 and 23, respectively, formed therein and similar slots 27 and 28 (Fig. 4) are formed in the flanges l1 and 18.

The shell l2 (Fig. 1) is designed to fit closely into a recess 24 formed in a heavy top mold section 25, and the shell l3 fits closely into a recess 26 formed in a heavy bottom mold section 30. A U-shaped clamp 31 (Figs. 1 and 2) having tongues 32 and 33 formed thereon can be slid over the flanges l1 and 20 to clamp the shells l2 and I3 together, when desired. A U-shaped clamp 34, identical with the clamp 3|, is adapted to clamp the flanges I8 and 2! together in a manner similar to that in which the clamp 3| clamps the flanges l1 and 20 together.

Pins 3838 (Figs. 1 and 4) projecting from opposite sides of the top mold section fit into notches 3939 formed in the lower mold section when the mold sections are assembled together. pins and the notches serve to align the mold sections so that the recesses 24 and 26 are aligned when the mold sections are assembled together. In the operation of the apparatus described hereinabove, the shell I3 is placed in the recess 26 in the bottom mold section 30, and strips 37-}? of vulcanizable material such as a rubber or rubber-like compound are wrapped around the loading coil I!) mounted on the cable II and around the portions of the cable adjacent to the loading coil. The strips 3'l31 of vulcanizable material, the loading coil Hi and the cable H are placed in the cavity 14 with the cable I! resting in the grooves l5 and IS. The shell [2 then is placed in the recess 24 in the top mold section 25. The shell l2 fits snugly into the recess 24 and the friction therebetween prevents the shell l2 from accidentally falling out of the recess during movement of the shell and the top mold section. However, when it is desired to remove the shell l2 from the recess 24, the shell may be removed with ease. I

The mold section 25 and the shell l2 then are moved over the loading coil l0 and the cable ll. As the top mold section is placed over the lower mold section, the pins 38-38 fit into the notches 39-39 formed in the lower mold section, whereby the mold sections and the shells are aligned. The entire assembly then is placed in a suitable vulcanizing press 50 (Fig. 4), which presses the top mold section 25 toward the bottom mold section 30 and heats the mold sections 25 and 30 to a Thehigh temperature, whereby the mass of vulcanizable material is vulcanized under pressure.

After the strips 31-31 have been molded into a single mass 5i (Fig. 5) of vulcanized material, the clamp 3i. (Fig. 2) is placed over the flanges l! and to clamp these flanges together, and the clamp 34 is placed over the flanges it and 2i to clamp those flanges together. The press 58 (Fig. 4) then is opened, and the entire assem bly is withdrawn from the press. The mold then is raised from the shell l2 and the shells l2 and I3 are lifted from the mold section .35. The shells l2 and 13, while they still are clan'lpedv together by the clamps 3i and 33, are insertedin a tank 52 (Fig. 3) containing a quantity of Water, whereby the vulcanized mass of vulcanizable material is cooled and any hot gases contained in the mass of vulcanizable material, are cooled so that the gases will not burst the vidcanizable material when the shells l2 and 13 are removed therefrom.

An alternate set of shells (not shown) which are identical with the shells l2 and i3 then are placed in the hot mold sections and 3B and the shells and mold sections are assembled over another cable and loading coil wrapped with strips of vulcanizable material. This assembly then is placed in the press, and the press is closed to vulcanize the last-mentioned strips of vulcanizable material.

After the mass of vulcanizable material has been cooled, the clamps 3i and 34 are removed from the flanges l1 and 2%, and i8 and 2!, respectively, and the shells IZ'and l3 are separated. The molded article then is removed from the shells, after which another molding operation similar to that described hereinabove may be conducted with the shells l2 and i3 being substituted for the alternate set of shells. Ii necessary; more than one alternate set of shells may be used with the mold sections 25 and 38.

In the operation described hereina-bove, only the thin shells l2 and l3 or the alternate set or sets of shells are cooled, and when another molding operation is started, the thin shells are the only portions of the apparatus which must be reheated from a low temperature, the heavy m ld sections 25 and 36 retaining almost all of the heat of the previous vulcanizing operation. However, the shells serve to maintain the mass of vulvanizable material under a high pressure after the material has been vulcanized so that any gases formed in the article being vulcanized as it is heated by the vulcanizing operation are not free to burst through the mass ofvulcanizable material prior to the cooling step. When the article is cooled, the gases are cooled and do not burst the cover of vulcanized material after the shells l2 and I3 are removed therefrom.

What is claimed is: V

1. In a molding apparatus including a pair of heavy mold sections having elongated recesses formed therein, means comprising a pair of thin rigid inserts fitting into the recesses and extending beyond the ends of the mold sections, said inserts having complementary molding cavities formed therein and being removable from the heavy mold sections, and means for clamping the ends of the inserts together so that the inserts are held together as they are removed from the heavy mold sections.

2 in a moldi g apparatus including a pair of complementary mold sections having compleinentary recesses formed therein, the improvement which comprises a pair of rigid shells havingfiangeson the ends thereof and designed to fit closely into the recesses with the flanges projecting beyond the recesses, said shells having complementary molding cavities formed therein for retaining the elements of an article to be molded therein, said flanges being provided with grooves therein, and a pair of U shaped clamps designed to enter the grooves in the flanges for clamping the shells together at the flanges thereof. 7

3. In a molding apparatus including a pair of complementary mold sections having complementary elongated, tapered recesses formed therein, the improvement which comprises a pair of rigid shells having flanges on the ends thereof, designed to fit closely into the recesses with the flanges extending beyond the recesses, said shells having complementary molding cavities enlarged at the central portions thereof, tapering to semicylindrical grooves at the ends thereof and also being provided with grooves in the flanges thereof for providing clearance'for a core, and a pair of U-shaped clamps tor clamping the shells togather at the flanges thereof.

A IN N. GRAY.

REFERENCES CITED The following references are of record the file of. this p ent:

UNITED STATES PATENTS Numbe Name Da 484.3% Smith Oct. 11, 1892 1,3310% Kempton Feb. 24, 1902 1,438,160 State Dec, 5, 1922 17,481,895 Gammeter Jan. 29, 1924 1,935,794 Geyer Nov. 21, 1933 2,3l'7,.5,$.7 Ford etal. H Apr. 27, 1943 2,329,867 Whitehead Sept. 21, 194 2,336,578 .sko lne Dec. 14, 1943 

